This invention relates to the filling and sealing of containers having fill ports such as electrolytic cells and specifically batteries. The invention was specifically developed for and has found utility in the filling and hermetically sealing of batteries intended for powering medical devices.
The battery's components are usually encapsulated in a metal container the top of which is closed by a metal header. The header typically has a fill port formed therein which provides a cylindrical passageway through which liquid components are introduced into the container. 304L stainless steel is a typical container and header material although there are many grades of stainless steel which may be used. Following placement of mechanical components and any solid chemical constituents in the container, the header is welded to the container top. The container is then filled with a liquid constituent through the header fill port which is then hermetically sealed. The hermeticity or perfection of seal at the fill port is an important feature in high reliability cells.